Joseph Hosny, 57, was previously awarded $325,000 for the assault after claiming he suffered post-traumatic stress following the attack by actor Jason Gann on Derby Day at Flemington Racecourse in 2007.

Mr Gann has refused to make the $325,000 payment or Mr Hosny's legal fees, which exceed $200,000, after relocating to Los Angeles after his program Wilfred became a smash hit in the US.

The decision in the Melbourne Magistrates' Court on Monday would derail the payment to Mr Hosny, his barrister Simon Kenny said.

"A finding of guilty in this matter will be fatal to the conduct of those proceedings," Mr Kenny said.

Magistrate Peter Reardon gave Mr Hosny a six month jail term suspended for two years in the Melbourne Magistrates' Court on Monday after Mr Hosny pleaded guilty to obtaining $49,787 in WorkCover payments by deception.

Mr Hosny was fortunate with the Victorian government's abolition of suspended sentences coming into effect on Monday, but not being applied to retrospective cases.

Magistrate Reardon said because the offences were committed before the changes came into place, a suspended sentence was warranted.

Mr Hosny was driving a full shuttle bus at the spring racing carnival in 2007 when he told Mr Gann and his girlfriend they would have to wait for the next bus.

The drunken actor, who spent the afternoon in a VIP lounge, abused Mr Hosny before punching him repeatedly in the face as other passengers tried to restrain him.

Mr Gann previously told Fairfax Media the St John's Ambulance report on the day of the incident found there were no physical injuries from the assault and he questioned the psychiatrist's report that found Mr Hosny could never return to work.

Mr Kenny told the court on Monday that Mr Hosny returned to work a week later, with his mental health deteriorating to the point he went onto WorkCover four months later with post-traumatic stress disorder.

Mr Gann welcomed the verdict from Los Angeles.

"I am pleased that this fraud has now been acknowledged by Mr Hosny and the court. It means civil action against me was based on a lie. I can now reassess my legal options," Mr Gann said.

Prosecutor Peter Matthews said Mr Hosny made "calculated" lies to doctors and WorkSafe for 18 months, continually signing documentation that stated he was unfit for work when he sporadically worked for the Victorian Racing Club.

It was Mr Hosny's own doing that unravelled his lies, the court heard, with the civil action he launched against Mr Gann and the failed proceedings against the VRC to obtain money for damages shedding light on the fraud.

The court heard Mr Hosny had been "somewhat homeless" for the last two years and lives in a facility run by mental health organisation MIND, still receiving $464 a week in WorkCover payments. He has no assets, no car and no savings.

Magistrate Reardon said what Mr Hosny did was "akin to welfare fraud".

"You chose to be devious about the matter," he said.

He ordered Mr Hosny to pay back the Work Cover compensation and court costs.